White-collar jobs were once deemed mostly immune to such automation, but that is no longer true, either. Carl Benedikt Frey, an economist, and Michael Osborne, a professor of machine learning, at Oxford University estimate that about half of American jobs — sailors, paralegals, you name it — are susceptible to automation. “Software substitution, whether it’s for drivers or waiters or nurses” is coming, Bill Gates said recently at the American Enterprise Institute in Washington. “Twenty years from now, labor demand for lots of skill sets will be substantially lower. I don’t think people have that in their mental model.”